1. Field of the Invention
The present invention generally relates to a tracking device, and more particularly, to a solar tracking device.
2. Description of Related Art
The sun provides a virtually unlimited and pollution-free supply of solar energy, and along with the increasing concern regarding pollution and power shortage, solar energy has become the focus among all power sources. A solar panel can convert solar energy directly into electric energy because it is disposed with a photovoltaic cell (PV cell). However, how to increase the photoelectric conversion efficiency of a solar panel is one of today's major subjects.
Generally speaking, compared to a solar panel facing a fixed direction, the photoelectric conversion efficiency of a solar panel which faces the sun all the time is greatly increased by 25%˜40%. However, every day the sun moves from east to west due to the axial rotation of the earth, and because there is a 23.5° inclination between the rotation axis of the earth and the revolving orbit thereof around the sun, the yearly movement of the sun is meridional. In other words, a solar tracking device having more than one axis has to be adopted in order to allow a solar panel to face the sun more effectively and to achieve a higher photoelectric conversion efficiency.
A control motor or an equivalent control unit is usually adopted in an existing solar tracking device for controlling the movement of a solar panel. In order to allow a solar panel to face the sun correctly, photo sensors are usually disposed in a conventional solar tracking device for detecting the maximum solar radiation intensity of the sun at all the time, such that the movement of the solar panel can be adjusted in real time to orient the solar panel towards the sun.
However, because a conventional solar tracking device is usually disposed with multiple photo sensors, the operation mechanism thereof is very complicated and the fabricating cost thereof is very high.